Phil Mickelson reacts after missing his birdie putt on the first playoff hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)— AP

Phil Mickelson reacts after missing his birdie putt on the first playoff hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)
/ AP

Keegan Bradley reacts after missing his birdie putt on the second playoff hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)— AP

Keegan Bradley reacts after missing his birdie putt on the second playoff hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)
/ AP

Keegan Bradley celebrates his birdie putt in regulation play that put him in a three-way tie for the lead, and an eventual tie for second in a playoff, in the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Reed Saxon)— AP

Keegan Bradley celebrates his birdie putt in regulation play that put him in a three-way tie for the lead, and an eventual tie for second in a playoff, in the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Reed Saxon)
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Phil Mickelson reacts after three-putting the 15th hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)— AP

Phil Mickelson reacts after three-putting the 15th hole during the final round of the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)
/ AP

Bill Haas holds the winner's trophy after his victory in the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Reed Saxon)— AP

Bill Haas holds the winner's trophy after his victory in the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Reed Saxon)
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Bill Haas hugs his wife, Julie, after winning the Northern Trust Open golf tournament on the second playoff hole at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Chris Carlson)— AP

Bill Haas drives on the second tee on his way to victory in the Northern Trust Open golf tournament at Riviera Country Club in Los Angeles, Sunday, Feb. 19, 2012. (AP Photo/Reed Saxon)
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LOS ANGELES 
The 18th hole at Riviera had given up only six birdies to 73 players in the final round of the Northern Trust Open. Bill Haas convinced himself there would be at least one more to force a playoff.

The surprise was how it ended.

Two holes after Phil Mickelson and Keegan Bradley poured in birdie putts to set up a three-man playoff, Haas won with a birdie on the 10th hole when all he was trying to do was make par.

It was just under 45 feet, all the way across the shallow putting surface, and it provided a stunning conclusion right when thousands of delirious fans - including Jerry West, the tournament's executive director - thought it couldn't get any better.

"If I hit 30 putts, I maybe make five of them," Haas said. "But it just so happens it did right there. I hit it just like I wanted. I hit the line. There was a ball mark about 10 feet in front of me. I was trying to go just around that, and I did that.

"I'm not giving it all to luck," he said. "I felt like I hit a nice putt. But from that length, anything can happen."

On this day, just about everything did.

Haas started the final round two shots behind, making him the fourth consecutive PGA Tour winner rally on Sunday. He holed a 5-foot par putt for a 2-under 69 that looked like a winner when neither Mickelson nor Bradley, who shared the 54-hole lead, birdied the par-5 17th and came to the last hole needing a birdie to keep playing.

Haas was on the practice range at 7-under 277 and a one-shot lead, preparing for a playoff that seemed unlikely. What followed were two putts that even impressed West, the Los Angeles Lakers great known as "Mr. Clutch," who was standing with thousands of fans on the hill below the fabled clubhouse at Riviera.

Mickelson had missed three straight putts inside 10 feet on the back nine - two for par, one for birdie - and just when it looked as though he had lost all hope, he rammed in a birdie putt just outside 25 feet from off the green, pointed his putter toward the cup and slamming down his fist when it fell for an even-par 71.

"I kept fighting, and I was giving away shots and was trying to let it go and move on and see if I could capture one, and I finally got one to go on 18," Mickelson said. "It felt great."

He bumped fists with Bradley and told him, "Join me."

Bradley, the PGA champion, did just that. His putt from about 12 feet took one last, slow turn and disappeared for a 71.

"Even though I didn't win the tournament, to make that putt on the last hole, one of the toughest holes on the PGA Tour, is really awesome," Bradley said.

They started the playoff at the 18th. Haas was short of the green, 80 feet away, and hit a chip-and-run to 3 feet for par. Mickelson two-putted from 35 feet and Bradley's 15-footer from just off the back touched the right side of the cup.